/**
 * @file ringbuff.h
 * @author zdk
 * @brief 用于缓冲串口收到的字节数据的环形缓冲
 * @version 0.1
 * @date 2021-08-08
 * 
 * BSD 3-Clause License
 * 
 * Copyright (c) 2021, water_zhang
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * * Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 * 
 * * Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * 
 * * Neither the name of the copyright holder nor the names of its
 *   contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 */

#if !defined(RINGBUFF_H)
#define RINGBUFF_H

#include <stdint.h>

#define RINGBUF_MAX_LEN (128)

typedef struct ringbuf_def
{
    char buf[RINGBUF_MAX_LEN];
    uint8_t wr_index; /* 指示下一个写位置 */
    uint8_t rd_index; /* 指示下一个读位置 */
} ringbuf, *ringbuf_t;

#define ringbuf_init(_obj_)                        \
    do                                             \
    {                                              \
        (_obj_)->wr_index = (_obj_)->rd_index = 0; \
    } while (0)
#define ringbuf_is_empty(_obj_) ((_obj_)->wr_index == (_obj_)->rd_index ? 1 : 0)
#define ringbuf_is_full(_obj_) (((_obj_)->wr_index + 1) % RINGBUF_MAX_LEN == (_obj_)->rd_index ? 1 : 0)
#define ringbuf_push(_obj_, data_ptr)                                  \
    do                                                                 \
    {                                                                  \
        (_obj_)->wr_index = ((_obj_)->wr_index + 1) % RINGBUF_MAX_LEN; \
        (_obj_)->buf[(_obj_)->wr_index] = *(data_ptr);                 \
    } while (0)
#define ringbuf_pop(_obj_, data_ptr)                                   \
    do                                                                 \
    {                                                                  \
        (_obj_)->rd_index = ((_obj_)->rd_index + 1) % RINGBUF_MAX_LEN; \
        *(data_ptr) = (_obj_)->buf[(_obj_)->rd_index];                 \
    } while (0)

#endif // RINGBUFF_H
